There is a startup out of Raleigh, NC that's trying to solve this exact problem.
deja Mi has built an iPhone app that allows you to capture media and upload it to a collection of media assigned to the specific venue or event you're attending. You can hear the spiel straight from the horse's mouth here: http://www.mycarolinatoday.com/2011/07/deja-mi/
On a side note, for those local to the Triangle, NC there's going to be free concerts throughout the weekend in downtown Raleigh to kick off the release of their app. The lineup of musicians is very impressive, go check it out if you're able. More details: http://dejami.com/dejafest